• Journal of Korean Society of Steel Construction
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• v.23 no.1
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• pp.41-49
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• 2011

A long-span (more than 8m) plastic greenhouse is currently being used in farms due to its magnified benefits, such as the convenience of the farming equipment used, and the land usage efficiency. In this study, the reinforcing effects of the use of a pretension tie were shown. In a previous study, tests for a 6.5m single-span-type greenhouse announced by Rural Development Administration were carried out. The tests of symmetric and eccentrics now loading by the sun and wind were conducted for the 10.2m span with a ${\phi}48.1{\times}2.1$ section in this study, after which the load-deflection relationship was compared for the cases of reinforcement with a tie and without a tie. The results of the symmetric snow loading test showed that the strength increased by 68~93% in the case of the specimen with a tied arch. The failure mode of the specimen without a tie tended to be that with a sway failure mechanism, and that of the reinforcement specimens with a tie tended to be that with an arch buckling mechanism. The results of the eccentric snow loading test showed that the strength of the specimen with a tie increased by 10~20% compared to that of the specimen without a tie. For the failure mode of the latter, a combined failure mechanism was adapted, although the failure mode of the tied specimens tended to be that with an arch buckling mechanism.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.2
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• pp.237-248
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• 1993

Although pantograph has been used to investigate whether the determinents of the mandibular movement were possible contributing factors of TMJ click, there was the problems to understand the role of tooth morphology upon the occurrence of click because of using appliance without tooth contacts. There Were advantages to evaluate the effects of tooth morphology upon the mandibular movements, because intraoral tracing device(Functiograph$^{(R)}$) had been obtained maintaining occlusal contact between the upper and lower natural teeth during mandibular movement. The purpose of this study was to record the mandibular eccentric movement quantitatively performed in 20 adult control subjects and 20 adult subjects with TMJ click and to investigate the effects of occlusion upon the occurrence of TMJ click. The obtained results were as follows : 1. The average ICP-P distance was $3.07{\pm}0.73mm$ in subjects with TMJ click, $2.14{\pm}0.85mm$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.001). 2. The average ICP-P distance was $3.07{\pm}1.14mm$ in subjects with TMJ click, $2.61{\pm}0.96mm$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.05). 3. The average distance of right and left lateral movement was not statistically significant between subjects with TMJ click and control subjects. 4. The average lateral displacement from midline during RCP was $0.75{\pm}0.54mm$ subjects with TMJ click, $0.16{\pm}0.17mm$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.001). 5. The average lateral displacement from midline during protrusive movement was $0.88{\pm}0.54mm$ in subjects with TMJ click, $0.20{\pm}0.23mm$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.001). 6. The average angle of right and left lateral movement was $144.2{\pm}20.20^{\circ}$ in subjects with TMJ click, $138.15{\pm}20.09^{\circ}$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.05).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.596-603
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• 2020

'Electro-Mechanical Brake (EMB) is a novel braking system for automobiles and railway vehicles, and research in this area is actively underway. The current braking system for railway vehicles generates a braking force using a pneumatic cylinder, but the EMB system generates the force through a combination of an electric motor and gears. In this study, the design of an EMB system that meets the domestic standards was conducted through the finite element modeling and fatigue analysis of an eccentric rotating shaft-based EMB system capable of generating a high clamping force. At this time, to improve the accuracy of fatigue analysis, three types of fatigue test specimens, which were subjected to the same heat treatment as the materials used in the prototype, were produced, and the fatigue tests were performed for each material. The fatigue properties (S-N curves) were obtained from the fatigue test results for each material and reflected in the analysis model. The results of fatigue analysis confirmed that the design of the EMB prototype could satisfy the maximum commercial braking/relaxation of 530,000 times, which was the endurance life condition for domestic railway vehicles. In addition, based on this design, a prototype will be manufactured, and endurance testing will be completed to demonstrate the durability characteristics of the developed prototype.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.1
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• pp.91-101
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• 2008

Structural analysis models to develop live load distribution factors of simply supported prestressed concrete I-girder bridge should have the precision of the analysis results as well as modeling simplicity. This is due to the numerous frequency of structural analysis needed while developing live load distribution factors. In this study, an appropriate structural analysis model is selected by comparing previous researchs studies and models used in practical design. Also, the influence by the flexural stiffness of barrier and diaphragm on the live load distribution had been analyzed through comparing the numerical analysis and experimental tests. As a result, the model that the eccentric girder and the barrier and diaphragm are connected to the deck plate was appropriate in satisfying both accuracy and simplicity for structural analysis of simply supported prestressed concrete I-girder bridge. However, the barrier was analyzed to have insignificant influence on the live load distribution in spite of its variation of stiffness. The eccentric diaphragm showed little influence at 25% or higher of flexural stiffness. From the results, a model that the girder is rigidly connected to the deck plate in consideration of the eccentricity, the barrier is ignored and the whole section of diaphragm is supposed to be valid without eccentricity is decided as the most appropriate structural model to develop the live load distribution factors of simply supported prestressed concrete I-girder bridge in this study.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.6
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• pp.902-910
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• 2008

A view of the Orientalism that sees the Orient as the inferior Other, characterized by the heterogenic, eccentric, backward, and passive features, has been internalized in the unconsciousness of Westerners. 'Orientalism' which is the cultural device and the system of discourse to put Asia in the fixed frame of dominance was the West European centered term, designating Southwest Asia including South Europe and North Africa as Orient, and contained the idea that non-Western society could progress only with the acceptance of Western civilization. Accordingly, it is need to use this term deliberately. In addition, even though the Asian Look of the West, borrowing the images and costume styles of Asia has lost the original mentality of Asia, it was not initiated from the perception that sees Asia as the inferior Other. Since the Asian Ethnic Look is the Western costume, borrowing the image of Orient and style by being fascinated by Oriental Aesthetics, the attributes of it are different from those of Orientalism. Therefore, it is not appropriate to designate the Asian Ethnic Look as 'Orientalism Fashion' or 'Oriental Look' except for some eccentric manipulation of Asia costume and image. Instead, it is desirable to exchange the term 'Asian Look', 'Asian Fashion', and 'Asian Ethnic Look' upon occasions or the name of individual nation or region can be referred to as preferred alternatives. Today, Asia including Korea is taking the initiative in the World Fashion as one of central axes of World Fashion Industry, and cannot be interpreted from the perspective of West Centrism. Now, it's time to dissolve the dichotomous prejudice of the West centrism on Asia's own strength.

• Journal of Korean Society of Steel Construction
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• v.26 no.1
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• pp.43-53
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• 2014

A single plate connection(SPC) consists of a plate welded to the columns and bolts connected to the beam web. The SPC is widely used for a simple shear connection of steel structure because it is easy-to-fabricated, easy-to-installed and economical. The conventional SPC is used for 2 to 12 bolts in a single vertical row. It is designed to limit the plate thickness by bolt diameter to obtain flexible and ductile connections. The design strength for eccentric shear shall be the lesser of the shear strength of bolts or bearing strength of plate and when the design strength is decided by edge distance failure, the results can be very conservative. Although the research on special solution for 'weak-plate/strong-bolt' model with 2 to 4 bolts has been conducted by L. S. Muir, and W. A. Thonton, 2004, study on generalized design procedures did not conduct. This study proposed design procedure for evaluation of the design strength of eccentric shear bolt groups on a single plate connection based on the actual edge distance and the direction of bolt reaction forces by using elastic vector method(EVM) and instantaneous center of rotation method(ICM).

• Journal of Korean Society of Steel Construction
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• v.19 no.2
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• pp.233-245
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• 2007

Previous finite element studies have shown that AASHTO Standard load distribution factor (LDF) equations appear to be conservative for longer spans and larger girder spacing, but too permissible for short spans and girder spacing. AASHTO LRFD specification defines the distribution factor equation for girder spacing, span length, slab thickness, and longitudinal stiffness. However, this equation requires an iterative procedure to correctly determine the LDF value due to an initially unknown longitudinal stiffness parameter. This study presents a simplified LDF equation for interior and exterior girders of two-span continuous I-girder bridges that does not require an iterative design procedure. The finite element method was used to investigate the effect of girder spacing, span length, slab thickness, slab width, and spacing and size of bracing. The computer program, GTSTRUDL, was used to idealize the bridge superstructures as the eccentric beam model, the concrete slab by quadrilateral shell elements, steel girders by space frame members, and the composite action between these elements by rigid links. The distribution factors obtained from these analyses were compared with those from the AASHTO Standard and LRFD methods. It was observed through the parametric studies that girder spacing, span length, and slab thickness were the dominant parameters compared with others. The LRFD distribution factor for the interior girder was found to be conservative in most cases, whereas the factor for the exterior girder to be unconservative in longer spans. Furthermore, a regression analysis was performed to develop simplified LDF formulas. The formulas developed in this study produced LDF values that are always conservative to those from the finite element method and are generally smaller than the LDF values obtained from the AASHTO LRFD specification. The proposed simplified equation will assist bridge engineers in predicting the actual LDF in two-span continuous I-girder bridges.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.4
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• pp.253-261
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• 2018

Purpose: The purpose of this study was to analyze correlation between bruxism and occlusal contacts on balancing side. Materials and Methods: The purpose of this study is to compare the difference of group function and balancing side occlusal contacts according to bruxism and sex, A total of 100 adults that aged 26-37 years (39 bruxers and 61 non-bruxers) were examined. The lateral excursion and balanced occlusal contacts were analyzed to determine the correlation with bruxism. The occlusal contacts were recorded by T-Scan system and articulating paper. Results: The group function was the highest in 61.5% of bruxers and 47.5% of non-bruxers. In comparison between males and females, group function was 58.9% in males and 37.0% in females. Occlusal contacts on non-working side occurred in 48 out of 100 patients. There were 51.2% of the cases in the bruxers and 46.0% in the non-bruxers. Statistically, there was no correlation between the bruxism and occlusal contacts on non-working side. There was no correlation between sex and balancing occlusal contacts. Conclusion: There was no significant correlation between bruxism and occlusal contacts on non-working side. The group function was the highest in bruxers when lateral excursion was occurred.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.3
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• pp.95-104
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• 2007

This study was focused on the effect of concrete strength and lateral ties of concrete columns subjected to eccentric compressive loads. The twenty-four concrete columns with $200mm{\times}200mm$ square cross-section were tested. The main variables were concrete strength, spacing and configuration of lateral ties, and eccentricity ratios. From the experiment, the followings were investigated ; 1) In all cases, it was observed that the increase of concrete compressive strength led to the decrease of ductility. Also, as the eccentricity ratios increased, the effect of ductility enhancement by lateral ties decreased. 2) As the ties spacing decreased from 100mm to 30mm, the magnitude of axial load acting on the concrete column showed an enhancement of 1.1~1.2 times and the descending curve after a peak moment presented a smooth decline. 3) The high-strength concrete columns required a design of lateral ties to increase the volumetric ratios and density of tie spacing to sustain a proper strength and ductility. Accordingly, regardless of concrete strength, the current AIK design code to specify the maximum tie spacing of concrete columns was proven to lead to the poor strength and ductility for seismic design. Therefore, it is necessary to develop a new seismic design code that connects volumetric ratios and tie spacing of concrete columns with concrete strength.

• Earthquakes and Structures
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• v.4 no.4
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• pp.429-449
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• 2013

Current Design Codes for Reinforced Concrete (RC) interior beam-column joints are based on limited experimental studies on the seismic behavior of eccentric joints. To supplement existing information, an experimental study was conducted that focused on the effect of eccentricity of the deeper beams with respect to the shallow beams. A total of eight one-third scale interior joints with beams of different depths were subjected to reverse cyclic loading. The primary variables in the test specimens were the amount of joint transverse reinforcement and the cross section of the shallow beams. The overall performance of each test assembly was found to be unsatisfactory in terms of joint shear strength, stiffness, energy dissipation and shear deformation. The results indicated that the vertical eccentricity of spandrel beams in this type of joint led to lower capacity in joint shear strength and severe damage of concrete in the joint core. Increasing the joint shear reinforcement was not effective to alter the failure mode from joint shear failure to beam yielding which is favorable for earthquake resistance design, whereas it was effective to reduce the crack width at the small loading stages. Based on the observed behavior, the shear stress of the joint core was suggested to be kept as low as possible for a safe and practical design of this type of joint.